Hydraulic shimmy damper for aircraft landing gear |
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IPC classes for russian patent Hydraulic shimmy damper for aircraft landing gear (RU 2527612):
 
 Telescopic adjusted-load shock absorber / 2364773
Invention relates to automotive industry, particularly to automotive shock absorbers. Proposed shock absorber comprises casing, cylinder, compensating chamber communicating, via throttling orifices, with the cylinder chamber, rotary controlled-from-outside ring to vary throttling orifice cross section, push rod, piston with bypass valve and blow-back valve, compression spring and guide bushing. Aforesaid rotary ring is fitted in the rod end and fixed to the compression spring end. The spring other end faces the piston and is fastened to the push rod. Ring surface in contact with the throttling orifice surface have various-cross section calibrated orifices. Turning the push rod in the guide bushing allow the channels to form, together with throttling orifices, through orifices with different cross section area.
 Multipurpose hydraulic shock-absorber for vehicle / 2290547
Shock-absorber comprises controlled means (70) and (71) that determine shock-absorbing in compression phase and are mounted in head (61) of tank and accessible from inside. Means (71) comprises tubular housing (75) for control of preliminary loading that is screwed in head (61) of the tank and provided with the outer control head (75a). Tubular housing (75) is made for permitting connection with the chamber with greater cross-section of the shock-absorber. Tubular housing (75) receives control screw (70) that passes through it in the axial direction and is screwed in its vertical top part. The end of the screw that enters the tank is provided with valve (72) provided with spring means for calibration and at least one radial groove (81) that defines leakage passage for determining preliminary loading. The cross-section of the passage is determined by the distance between face (82) of tubular housing (75) and inner side (61a) of head (61) of the tank.
 Shock-absorber for suspension of vehicle for arctic operating conditions / 2263835
Shock-absorber comprises housing, rod, piston secured to the rod and provided with throttling system, and hydraulic space filled with fluid. The piston separates the space into the top and bottom sections. The shock-absorber has switch connected with electromagnetic valve, indicating lamp, and pickup for measuring the temperature of fluid, which switches the indicating lamp and electromagnetic valve in or off. The housing is provided with casing provided with easily detachable heat insulating jacket. The space between the housing and casing is connected with the cooling system of the engine of a vehicle through the electromagnetic valve. The bottom part of the hydraulic space receives the compression damper provided with the compensator.
 Arctic shock absorber / 2256832
Arctic shock absorber comprises housing, rod, piston provided with a throttling system and secured to the housing, and hydraulic space filled with fluid and divided by the piston into the top and bottom sections. The shock absorber has switch and indicating lamp connected with it, heating unit, and pickup which measures the fluid temperature and controls the switch-in and switch-off of the indicating lamp and heating unit. The housing is covered with the heating unit and protected against the heat exchange with ambient by way of a casing made of heat insulating material. The compression damper is mounted inside housing at its bottom part and is provided with a compensator.
 Aneroid device for valves / 2006716
The invention relates to the field of engineering, particularly to shock absorbers of vehicles
 Vehicle adjustable shock-absorber (versions) / 2480644
Shock-absorber contains reservoir, hydraulic cylinder with compression valve, rod with piston. The piston is equipped with bypass valve and rebound valve. The casing of shock-absorber force control valve is tightly connected to the hydraulic cylinder and has outlet channel with shutoff element. The outlet channel is connected to the hole in hydraulic cylinder. The shutoff element is connected to the membrane. The membrane is mounted in membrane chamber made with the possibility of exerting external control influence on membrane. According to the first version membrane chamber is fixed on reservoir in shock-absorber. According to the second version membrane chamber is fixed on the casing of shock-absorber force control valve in shock-absorber.
 System for damping vertical vibrations of railway passenger car body / 2470201
Invention relates to railway transport. The system contains vertical hydraulic dampers installed under body. Each damper is made as piston pump with discharge and free-flow intercommunicating via throttle chambers for working fluid. The throttle is equipped with rod of variable cross-section with thrusts for end positions. Throttle rod movement drive is made as return spring and solenoid. Solenoid core is connected with throttle rod. Solenoid coils are attached to output terminals of control unit. Input terminals of control unit are connected with electric power source and oscillation frequency sensors installed on body in the area of each damper location. Control unit provides automatic change of end positions of throttle rod by solenoid electric power switching on or off according to indications of corresponding sensors of body vibration frequency.
 Flow control valve for hydraulic adjustable dampers / 2460914
Hydraulic damper comprises high-pressure tube 10. Piston 14 divides tube 10 into compression chamber CC and draft chamber CT communicated via piston 14. Hydraulic fluid tank 14 communicates with compression chamber CC. Control valve VC communicates draft chamber CT with tank 20 and comprises tubular case 40 with radial channel open toward tubular case inner chamber and tank 20. Locking rod 60 displaces axially in tubular case 40 between control valve open and closed position to communicate draft chamber CT with tank 20. Actuator A displaces locking rod 60 in tubular case 40.
 Hydraulic damper / 2457375
Proposed device comprises hollow case accommodating hydraulic cylinder to make working fluid chamber. Hydraulic cylinder piston and rod are arranged to produce piston and rod ends. Damping device is arranged between case and cylinder and furnished with cover coupled with structural element accommodating restrictor and safety valve to communicate said piston and rod ends with said chamber. Cover has annular groove with seal fitted therein and is arranged to make drain chamber communicated with aforesaid chamber. Annular groove with support and sealing elements fitted therein is arranged at structural element on rod side. Safety valve is made up of plunger with flanges and cylindrical guide housing locking element to move relative plunger flange for contact with seat arranged on structural element for communication of rod en with drain chamber and, further, with aforesaid chamber. Cover seal is made up of sealing scraper. Annular grooves in cover and structural elements are open toward drain chamber wherein adjusting washer with annular ledge is arranged to lock sealing scraper. Said locking element has toroidal grooves on working fluid flow path at safety valve open.
 Vehicle hydro pneumatic shock absorber / 2361134
Invention relates to automotive machine building, particularly, to automotive cushioning systems. The proposed shock absorber comprises hydraulic cylinder filled with working fluid and accommodating piston and rod, and hydraulic accumulator. The rod lower part is furnished with radial throttling orifices and spring-loaded control plunger with edge covering aforesaid orifices. The said radial throttling orifices are spaced along the rod length so that the said control plunger jumps the orifices in turn, thus gradually varying the total flow section. The control plunger is fitted in the piston, outside the working fluid flows, and can deviate from its normal position only under gravity.
 Controlled hydraulic shock absorber / 2316685
Controlled hydraulic shock absorber comprises telescopic hydraulic two-tube shock absorber. The rod of the shock absorber is made of a hollow rod provided with the flange having a groove for roller thrust bearing and vertical slots from the other side. The hollow of the rod receives the hollow rod of by-pass valve for permitting vertical movement. The top section of the rod is provided with trapezium right thread, and the bottom section is provided with the stop for the spring of the valve. The driven pinion is screwed on the threaded part of the rod of the by-pass valve. The bottom of the driven pinion abuts against the roller thrust bearing that is mounted in the groove in the flange of the hollow rod. The second driven pinion is screwed on the threaded part of the valve rod. The top side of the pinion abuts against the roller thrust bearing. The third roller thrust bearing is interposed between the driven pinions. The driven pinions engage the driving gears mounted on the shaft of the electric motor. The control unit is connected with the electric motor and receives the signal from the pickups of suspension vibration and velocity pickup.
 A pneumatic spring suspension vehicles / 2180715
The invention relates to mechanical engineering and for the creation of a pneumatic springs
 Shock absorber valve located between its lower and compensation chambers / 2509932
Valve (1) of a shock absorber includes trim (4) sliding in holder (6) of the trim, and base (8) supported from the shock absorber bottom. Holder (6) of the trim is retained with base (8) by means of elastic retention device (28) and has the possibility of being moved relative to base (8) between a compression position and an extension position. Holder (6) of the trim includes seat (10) and housing (12) located in base (8) under seat (10). Retention device (28) is rigidly installed with one of its sides on housing (12) of holder (6) of the trim and includes part (32) located under the lower side of base (8) and borne against it in the extension position of holder (6) of the trim. The shock absorber includes a piston, a compensation chamber enclosing the upper and lower chambers, and the above valve (1).
 Oscillation damping method and device for its implementation (versions) / 2482347
Inclination angle of relationship between resistance force modulus and deflection speed modulus of an elastic member is changed if current resistance force modulus differs from the specified value. The specified value of resistance force is changed depending on current deflection of the elastic member. The specified current value of resistance force is set so that it is directly proportional to modulus of current deflection of elasticity force, which is corrected to resistance force vector, of the elastic member of its static value. The device for implementing the method represents a hydraulic telescopic damper, in which the resistance force, the modulus of which depends on the modulus of deflection variation speed, is created during the suspension deflection variation. As per the first version, the damper includes a bar fixed at the compression chamber bottom. The bar has a four-sided variable cross-section in the working section of its length. At the damper compression, the bar is retracted into inner cavity of the stock. As per the second version, the damper includes two bars, as well as a compensating chamber that is separated from the compression chamber with a partition wall and partially filled with liquid. The bars are made in the form of a rotation body and installed inside the first and the second guide elements respectively with possibility of longitudinal movement.
 Vibration isolator / 2480643
Vibration isolator contains the first and the second base, bearing flexible element and hydraulic damper attached between bases and two retainers. Hydraulic damper is made in a form of cylinder with piston and rod. At the bottom front part of the cylinder there is a subsidiary cavity and installed valve and throttling element. The valve is designed for fluid passing from subsidiary cavity to under-piston cavity of the cylinder. Subsidiary cavity is connected to above-piston cavity of the cylinder by hydraulic channel. Throttling element is designed for fluid passing from under-piston cavity into subsidiary cavity with obtaining stepped characteristic of dissipative force. The first retainer is attached to the first base and pin-connected to the rod. The second retainer is fixed on the second base and pin-connected to the cylinder. These two connections provide horizontal location of hydraulic damper.
 Rolling stock hydraulic vibration killer / 2478054
Invention relates to rolling stock running gear, particularly, to structural elements of spring suspensions, namely, to hydraulic dampers. Proposed device comprises working cylinder with piston and rod, piston and above-piston head ends, reservoir, throttling components, check and safety valves. Piston hollow rod doubles as working fluid reservoir. Piston divides working cylinder into piston and above-piston chambers and comprises valve system. The latter comprises safety valve communicating above-piston chamber with rod inner space, check valve to communicate said inner space with piston chamber, and check valve to communicate piston chamber and above-piston chamber. Common orifice rated to definite hydraulic resistance to working fluid is arranged in safety valve.
 Damping device of torsion excitation of hollow drive shaft / 2469217
Device includes elongated element (7) that passes along inner space of drive shaft; at that, one end of element is fixed on one shaft end, and the other end of element is located at the other end of shaft and hydraulic damping device (11) fixed on the other shaft end for damping of vibrations of the other end of element (7). Damping device (11) includes cylinder-piston system (25) having the first and the second cylindrical hydraulic chambers (45a, 47a), tank (19) for hydraulic fluid and hydraulic circuit (29, 31, 33, 35), by means of which chambers (45a, 47a) are connected to hydraulic fluid tank (19). Damping device (11) is located so that any leak flow of hydraulic fluid from the first (45a) and the second (47a) chambers through the boundary line between piston and cylinder flows to hydraulic fluid tank (19).
Hydraulic damper / 2457375
Proposed device comprises hollow case accommodating hydraulic cylinder to make working fluid chamber. Hydraulic cylinder piston and rod are arranged to produce piston and rod ends. Damping device is arranged between case and cylinder and furnished with cover coupled with structural element accommodating restrictor and safety valve to communicate said piston and rod ends with said chamber. Cover has annular groove with seal fitted therein and is arranged to make drain chamber communicated with aforesaid chamber. Annular groove with support and sealing elements fitted therein is arranged at structural element on rod side. Safety valve is made up of plunger with flanges and cylindrical guide housing locking element to move relative plunger flange for contact with seat arranged on structural element for communication of rod en with drain chamber and, further, with aforesaid chamber. Cover seal is made up of sealing scraper. Annular grooves in cover and structural elements are open toward drain chamber wherein adjusting washer with annular ledge is arranged to lock sealing scraper. Said locking element has toroidal grooves on working fluid flow path at safety valve open.
 Self-propelled vehicle driver seat / 2381919
Proposed seat comprise base, carcass with cushion and back coupled via scissors-type guide device and vibro isolation device pivoted to carcass with the help of bracket. Vibro isolation device comprises damping element and pendulum-type suspension. Upper and lower bases of vibro isolation device make an opening for support plate to come out. One end of support plate is jointed to pendulum suspension, another one is connected with objected to be vibration-isolated. Casing upper base has opening for pendulum suspension rod to pass through. Diametre of said hole matches that of damping element inner cylindrical surface. Flexible element represents helical coil spring enveloping pendulum suspension threaded rod. Spring lower base rests upon movable circular flange of hydraulic damping element, while upper base thrusts against cover with thrust ring that enveloped aforesaid spring. Cover has a opening for pendulum suspension rod to pass through with diametre that matches that of damping element inner cylindrical surface. Damping element is formed by two coaxial cylindrical sleeves to form tight circular chamber. Upper part of said chamber is closed by sealed circular flange, while washer fitted in thrust ring and rigidly coupled with damping device upper base tightly closes lower part. Said circular chamber accommodates circular piston with throttling orifices made therein. Piston is coupled with circular flange by three tie rods. Pendulum suspension represents a threaded rod arranged coaxially inside damping element. It is coupled with support plate and with cover.
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FIELD: machine building. SUBSTANCE: damper comprises hollow housing (10), cylinder piston (20) with the piston head, which forms two active hydraulic cameras, rod and deflecting units. A hydraulic compensator (40) is made with the internal volume of fluid medium, which is much greater than the volume of fluid medium removed from the housing. A hydraulic manifold (30) is located between the housing and hydraulic compensator. The control manifold is connected to the hydraulic compensator and establishes the passage between cameras. Manifold contains the interchangeable hydraulic valves (CV1, RV1; CV2, RV2) of the cartridge type for throttling of fluid medium flowing from cameras into the passage, allowing fluid medium to flow freely into cameras from the passage. EFFECT: decrease of sensitivity to variations of oil temperature, absence of cavitation, simplification of damper adjustment. 4 cl, 3 dwg
The technical field to which the invention relates. The present invention relates to shimmy dampers, in particular shimmy dampers used in the chassis of the aircraft for damping oscillations of the nose wheel. The level of technology Shimmy is a complex oscillatory phenomenon, to the extent affecting the chassis of some of the aircraft that it could jeopardize the stability of the chassis. In the aviation industry there has long been the practice of equipping the chassis of shimmy dampers that prevent the emergence of divergent oscillations. This shimmy damper discussed in US 5224668. In several accidents, some very well known shimmy dampers have shown themselves unable to compensate for the shimmy phenomenon. It is believed that such shimmy dampers suffer from at least one of the following drawbacks: - very low damping factor due to insufficient hydraulic throttling as to provide a higher throttling would be required to protect the orifice screen that may be difficult to implement in known devices. - hydraulic throttling suffers from large geometric tolerances, because often bore the usual drilled holes instead of precision calibrated hole is; hydraulic throttling suffers from significant temperature fluctuations butter; - anticavitation valve are often made under the order, which complicates their replacement in case, if after testing you will need the high-frequency characteristics; - small amount of oil in the hydraulic chamber, when intensive shimmy oil heats up quickly, losing the damping capacity; - hydraulic compensator has a threaded connection with the body shimmy, which weakens the strength of the mechanical connection and can lead to vibration fatigue, as in the previous incidents. Disclosure of inventions The objective of the invention is to provide a shimmy damper with no cavitation, the damping characteristics which are very slightly dependent on oil temperature and which is easy to configure. According to the invention offers hydraulic shimmy damper, including: - hollow body with a cylindrical surface and two end walls defining an internal functional scope; piston with piston head, which germetezirujushie engages with the specified internal cylindrical surface forming the inside of the functional volume two active hydraulic chamber, the piston has a W is OK, protruding from the said piston head, which germetezirujushie moves along one of the said end walls; - rejecting means for rejecting the piston relative to the specified body in the direction of the original position, thereby moving the piston forward and backward relative to the specified starting position under the action of external forces; - hydraulic compensator with the available internal volume of the fluid, which is significantly greater than the volume of fluid removed from the housing when the piston moves forward and backward; hydraulic manifold located between the said casing and the specified hydraulic compensator and defines a channel between the said chambers, which is connected with the specified hydraulic compensator and which additionally are interchangeable hydraulic valve cartridge type for throttling the fluid coming out of these cameras in the specified channel, allowing fluid to pass freely into the said chamber from the specified bandwidth. Such hydraulic cartridge-type valves have internal screens to protect them from contamination by large particles. Due to the significant volume compensator grosseserrata those who learn the environment, removed from the body, creates only a slight temperature increase of the total volume of oil inside the damper shimmy. This makes the shimmy damper is much less sensitive to fluctuations in oil temperature during intense shimmy. In addition, the use of standard hydraulic valves cartridge type simplifies the replacement of these valves to adjust the throttle characteristics of the shimmy damper. The shimmy damper according to the invention can easily be adapted for different types of chassis and can be modified during the lifetime of the chassis, with changes in the characteristics shimmy chassis due to aging and wear. Brief description of drawings The invention will become more clear in the light of the detailed description of one of the specific embodiments of the invention with reference to the following figures: figure 1, which shows a perspective view of the shimmy damper according to one of the embodiments of the invention; figure 2, which shows a view in cross section along the line II-II of figure 1; figure 3, which shows the hydraulic diagram of the shimmy damper of figure 1. The implementation of the invention With reference to figure 1 hydraulic shimmy damper includes a housing 10 in which a piston 20 engages for translational movement along the longitudinal axis X. the Specified enclosure 10 sacrament hydraulic manifold 30, which in turn is fixed to the hydraulic compensator 40. The shimmy damper is installed on the hinge between the two relatively oscillating chassis components, one component is fixed to a specific case, while the other component attached to the specified piston 20. For example, the shimmy damper can be installed between dvuhtomnike passing between the cylinder gear and the piston gear. With reference to figure 2 indicated the housing 10 includes a hollow cylinder 11, which has an internal cylindrical surface 12 and the first end wall 13. The specified cylinder 11 is closed with its opposite side a second end wall 14, forming an internal functional camera. The piston 20 has a piston head 21, which germetezirujushie engages with the specified internal cylindrical surface 12 defining two hydraulic chambers C1 and C2 within the specified functional volume. The specified piston 20 also includes a stem 22, which protrudes from the specified piston head 21 and germetezirujushie runs along the specified first end wall 13. Although it is not shown here, the housing 10 and the piston 20 has a corresponding mechanical fasteners for attachment to relatively oscillating components in the chassis. The specified piston 20 is hollow, and the plunger 15, the grip is connected to the said second end wall 14, passes so that he germetezirujushie engaged with the inner surface 23 of the specified piston 20. The plunger 15 has a circumferential ledge forming the stopper 16 for coupling or holder 17 is spring mounted so that it germetezirujushie slithered around the specified plunger 15. The first spring 18 is held between the said first end wall 13 and the piston head 21, pressing the specified piston head in the direction of the holder 17 of the spring. The second spring 19 is held between the said second end wall 14 and the holder 17 of the spring, pressing the specified holder 17 of the spring in the direction specified piston head 21. Due to this specified piston head 21 and the holder 17 of the spring are pressed to each other. The hydraulic pressure in both directions from the specified piston head 21 and the action of the springs 18, 19 leads to the fact that the holder 17 of the spring abuts butt in the specified limiter 16, while the specified piston head 21 abuts butt specified in the holder 17 of the spring, thereby forming a source, a Central position of the specified piston 20 relative to the specified enclosure 10, as shown in figure 2. The specified piston 20 moves freely forward and backward along the longitudinal axis X consider is Ino specified starting position every time when external force is able to overcome the pressure and force of the springs. It should be noted that in the specified source position has a certain offset between the said piston head 21 and the specified limiter 16 which transfer the specified piston 20 in the direction indicated limiter 16. As most clearly shown in figure 3, the said casing 10 communicates via a fluid from the manifold 30 through the communication holes H1, H2. The specified manifold 30 defines a channel between the two cameras C1 and C2 passing through holes HI and H2, as discussed next. Figure 3 is similar elements shown schematically indicated by similar reference positions. You can distinguish the specified body 10 and the piston 20. You may also notice that the hydraulic compensator 40 includes a housing 41 in which a piston 42 is deviated by the spring 43, germetezirujushie slides in the housing, supporting the excess pressure across the damper shims so that there were no cavitate. This spring 43 may be a mechanical spring, as shown, or considerably easier gas stops. The specified expansion joint 40 has an interior volume which is considerably higher than the volume removed from the cameras C1, C2 during the movement of the specified piston 20. Between specified to posom 10 and the compensator 40 passes the specified hydraulic manifold 30, which determines the throughput channel between the holes H1 and H2, providing connections for fluid between the chambers Cl, C2, and specified compensator 40. At the exit of each hole HI, H2 in the specified manifold 30 includes a parallel combination of a shutoff valve and throttle valve (respectively CV1, RV1 and CV2, RV2)located so that fluid removed from one camera, blowing through the corresponding throttle valve as the associated shut-off valve is switched to the absence of flow, and fluid flowing into another chamber, passed through the shut-off valve as a shut-off valve means in the flow regime. Therefore, when the piston 20 moves in one direction, the volume in one of the cells is reduced, resulting in the fluid medium is removed from the camera in the specified channel 31, overcoming the pressure supported by the specified compensator 40, the volume of the other chamber increases, causing the fluid to flow into this chamber due to excessive pressure, supported by the specified compensator 40 in the specified bandwidth of the channel 31. Fluid removed from one camera, choked corresponding throttle valve, while the liquid entering into another chamber, when the covers only a small resistance, because the check valve in the flow regime has a large flow section. Any change in the flow rate between the removed fluid medium and flowing a fluid medium is aligned specified compensator 40. You can easily guess that when under the action of external forces specified housing 10 and the piston 20 begins periodic relative movement forward and backward, fluid is removed from one of these cameras and, therefore, is choked twice, providing damping of such periodic movement. These springs 18, 19 also determines the stiffness of the spring, whereby the shimmy damper resists external forces, which are proportional to the amount of movement of the specified piston 20 relative to the specified enclosure 10. It should be noted that in the depicted embodiment, the spring stiffness has a concrete value while moving the specified piston 20 in one direction or another with respect to the specified block 10. These valves CV1, CV2, RV1, RV2 are standard hydraulic valves cartridge type and, if necessary, adjust the shimmy damper can be easily replaced. The specified manifold 30 has an additional shut-off valve V3 to connect the specified bandwidth of the channel 31 with feeding hole 32, making the surrounding if necessary, the oil flow in the shimmy damper. The present invention is not limited to the above detailed description and includes any variants, does not extend beyond the boundaries defined by the claims. In particular, despite the fact that the housing and the compensator is preferably mounted on the specified split manifold, this manifold can be executed as a single unit with the specified case, but it is made with possibility of installation in it of the standard cartridge-type valves. 1. Hydraulic shimmy damper, including: 2. Hydraulic shimmy damper according to claim 1, in which the deflecting means include: 3. Hydraulic shimmy damper according to claim 1, in which these hydraulic valves cartridge type include a shutoff valve (CV1; CV2) and throttle valve (RV1; RV2), located in parallel in place of each connection for fluid between the specified manifold and these cameras. 4. Hydraulic shimmy damper according to claim 1, wherein said manifold further includes an additional shut-off valve (V3), located between the specified bandwidth channel (31) and the feed hole (32).
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